Health dimensions and sex differences in frailty among nursing home residents: a cross-sectional study in Bilbao, Spain

Background: Frailty is a geriatric syndrome characterized by increased vulnerability to stressors. Evidence on sex-specific determinants of frailty in cognitively intact nursing home residents remains limited. This study aimed to identify health dimensions associated with frailty in older women and men in nursing homes. Methods: A cross-sectional study was conducted in 11 nursing homes in Bilbao, Spain. 147 residents aged ≥ 60 years without cognitive impairment were assessed using the Tilburg Frailty Indicator, together with validated measures of functional status, physical performance, emotional status (anxiety and depression), and loneliness. Sex-stratified analyses were performed using Spearman correlations and multivariable linear regressions. Results: In women, total frailty was positively correlated with depressive symptoms, anxiety, and loneliness, and inversely correlated with functional status and physical performance (all p ≤ 0.012). In multivariable models, only depressive symptoms (B = 0.306; p = 0.011) and loneliness (B = 0.215; p = 0.002) remained independently associated with frailty. In men, total frailty was positively correlated with depressive symptoms and anxiety and inversely correlated with handgrip strength, functional status, and physical performance (all p < 0.001). After adjustment, depressive symptoms (B = 0.442; p = 0.004), lower handgrip strength (B = -0.066; p = 0.041), and poorer physical performance (B = -0.194; p = 0.022) remained independently associated. Conclusions: Frailty among nursing home residents is a multidimensional condition. The findings suggest potential sex-related differences in the factors associated with frailty, with psychosocial variables showing stronger associations in women and physical performance-related variables showing stronger associations in men.